The invention relates to a plug screwing-in device for barrels or drums.
Barrels and drums to be filled with liquids are, in a known manner, supplied with screwed-on plugs. It is, therefore, necessary to remove these plugs and screw them on again after filling. The barrels must be precisely aligned on a supply belt or the like of the filling mechanism, because there is otherwise a risk of the liquid flowing over the barrel and not into the bunghole. The opening and closing of bungholes is very labour-consuming in the case of the known filling mechanisms.
For closing the filling opening of a barrel or the like with the aid of a device for inserting and fixing a plug in the opening, a closing device is known in which both the device for inserting the plug and also the position determining device must be spaced from one another in such a way that they are freely movable upwards and downwards, as well as in accordance with polar coordinates with respect to a fixed point in a plane perpendicular to the upwardly an downwardly directed movement. In addition, this known device has a gripping device in order to prevent the free movement of the devices for inserting the plug and for determining the position. Furthermore, a drive mechanism is provided, which is suitable for the plug insertion and positioning, when the gripping device prevents the free movement, only in a linear manner and necessarily by a distance corresponding to that between the two devices. This closing device has a very large size. In order to obtain adequate stength for the precise mounting of the movable components, it is necessary for the construction to be very complicated. In addition, the energy requirement for operating this closing device is very great because on centering, the complete frame must always be pivoted about an axis on the support device (DOS No. 18 17 237).
In addition, a further known cover closing and container filling device has a very complicated construction and is very complicated to use (U.S. Pat. No. 29 83 089).
Furthermore, a device for closing containers with an eccentrically arranged spout is known, which is characterized by a prime mover, which can be moved between an inoperative position and an operative position in which a centering device carried by this prime mover engages in the periphery of the container cover wall, which has an eccentric spout in such a way that a rotary output shaft of the prime mover is brought and held in a position coaxial to the container. A scanning device which is held eccentrically by the shaft and as part of the latter is displaceable therewith about a periphery, whose centre point is located on the container axis and whose radius is equal to the spacing between the spout axis and the container axis, up to an engagement position with the spout, and by a sealing head held eccentrically by the shaft in a coaxial position to the scanning device and displaceable along its own axis between an inoperative position and an operative position in which there is engagement with the spout. This device permits the closing of containers with eccentric spouts, the position of the spout being scanned with a device which facilitates and accelerates said scanning operation. At the same time a further device ensures that the complete working cycle of the device takes place completely automatically. However, in order to perform all these functions, the known device has a plurality of complicated components (DOS No. 22 10 753).
Another known device for fitting screwcaps to the bungholes of barrels, with an air or beam vertically movable by a lifting device and pivotable about a vertical axis and with a centering device, as well as a closing device which, by pivoting the arm or beam, can be successively brought over the bunghole of a barrel, is constructed in such a way that the centering device is detachably connected to the arm by means of a receiving flange and on the latter is provided a holding tube with joints for detecting fingers on the outer wall, the shanks of said fingers being guided through openings in the holding tube casing and held together by means of an elastic ring of rubber or the like and whose surface portions remote from the holding tube are risingly convex towards the centre axis of said tube and with guide pins arranged coaxially to the centre axis of the tube, that centrally to the holding tube a centering mandrel can be vertically moved up to engagement with the shanks of the detecting fingers through an opening in the receiving flange by means of a pneumatically or hydraulically acting lifting cylinder, and that the closing device has a suction head for exposing the barrel closure cover to a suction action and a screw head for screwing said cover on to the thread of the bunghole support located on the bunghole on which is arranged an end portion of a receiving tube, whose other end portion is fixed to a rotary drive shaft. Such a device is intended to make it possible not only to position the closing cover on the bunghole after filling the vessel and then screw it down, but also to bring about the necessary motion and force transfer processes by means of hydraulically or pneumatically acting control elements without using long and difficultly manufacturable threaded spindles or the like, so that even with small constructional sizes high power levels can be transferred (DAS No. 25 40 864).